Spark-plug



S. P. WELSH d amwz/m LMMQ,

STATES SAMUEL-P. WELCH, or ATLii-NTIc CITY, new JERS Y, Assreuon To cans sienna PLUG wonxs, or ATLANTIC CITY, NEW JERSEY,.A rasrnnnsnirr ceivrrcgn oracrnv BURT AND SAMUEL r. WELCH.

SPARK-PLUG.

Specification of Letters Patent.

?atented Aug. it 159%? Application filed July 12, 1919. Serial No. 310,514.

To all whom it may cancer-n Be it known that I, SAMUEL P. WVELGH, a citizen of the United States, residing at Atlantic City, in the county of Atlantic and State of New Jersey, have invented new and useful Improvements in Spark-Plugs, of which the following is a specification.

This invention relates to spark plugs employed in connection with internal combustion engines for igniting the fuel charges in the cylinders, and its'object is to provide a novel and improved plug in which the sparking terminals are arranged to produce more than one spark as will be described in detail hereinafter and claimed. In order that the invention may be better understood, reference is had to the accompanying drawing forming a part of this specification, and in said drawing,

Figure 1 is a central longitudinal section of the plug, and

Fig. 2 is a perspective view of a fragment of the core of the plug.

Referring specifically to housed in the usual metallic base shell 6 which is. constructed to screw into the eugine cylinder. The usual lock nut 7 is also provided for holding the core in the shell. These parts are all of standard design and construction, and hence a further description thereof is not deemed necessary.

The core 5 is made of porcelain, mica or other suitable insulating material, and in it is embedded the main electrode rod 8 projecting from both ends thereof, its outer end being provided with the usual means for connection of the current wire.

At the inner or cylinder end of the -core 5, the latter carries two conducting rings 9 and 10, respectively, said rings encircling the core and beingv fixed thereto in any suitable manner. The ring 9 has an electrode branch 11 extending downward and laterally to come opposite the end of the rod 8, and spaced from the latter a distance to enable the electric current to jump across the gap. The ring 10 is not in contact with the ring 9 and it is located back of the latter such a distance that the current can jump the gap between the two rings. From thering 10 the current jumpsthe gap between the same and the inner or cylinder end of the shell 6, this end of the shell the drawing 5 denotes the core of theplug, the same bemg encircling the ring in spaced relation. lit will be noted that the current cannot jump from the ring 9 directly to the shell 6 the d1stanceis too great and the ring 10 is also located directly between the ring 9 and the shell, in view of which it will be evident that the current entering the ring 9 must jump first to the ring 1i) and then to the shell 6. l

The plug produces three separate and distinct series sparks, the first spark occur.- ing between the electrodes 8 and ii, the next between the rings and 10, and the last between the ring 10 and the grounded shell 6., One or more sparks are assured, and if one or two gaps get clogged with carbon or oil, the plug is not stwrt-circuited rapid, with an attendant saving of luel and an increase of power an a better running of the, engine- It will be noted that the ring 10 is larger and has a greater crosssectional area than the ring 9. The ring 10 is therefore a better conductor than the ring 9 and as it is outside thelatter it attracts the current in a lateral direction, and as the shell surrounds the ring it), the current is again drawn in a lateral direction across the gap between said ring and the shell. The heat ing effect of the sparks on the fuel is therefore in a direction to cause expansion. in the direction of the piston travel instead of transversely thereof. As the ring 10 is in. side the shell 6, the current is induced to jump to the nearest ground which is the shell, and the spark once more passes through the fuel charge by jumping straight across the bottom of the plug to the shell. I

The ring 9 is adjustable to the main electrode 8 by bending the point 11, and this first gap maybe closed entirely without affecting the other gaps, if the ignition sys-,

can be made on the core 5 betore inserting the same into the shell 6.

I claim:

1. A spark plug comprising an insulating core a metallic shell carrying the core,

a main electrode rod carried by "the core,

A spark plugcrumprisiu; an inrnlating core, a metallic shell carr \'in; the core.

a main electrode rod carried by the ore, and a pair of conductor rings carried by the core and spaced to produce a sparl gap between said rings, one of the. rings being positioned with respect to the terminal of the main electrode rod to produce a spark gap between said ring and the rod. and the other ring being spaced iroin the shell to produce a spark gap between said ring: and the shell, said last nientioned ing having a greater conductivity than the first mentioned ring.

In testimony whereof I affix my signature.

SAMUEL P. WELCH. Witness:

F. A. JONES. 

